During exam preparation I found something, that can be wrong.
I think, there is an error in the UserPrincipalName parameter. It must be aylak@fabrikam.com.
* http://technet.microsoft.com/en-us/library/jj673532%28v=exchg.150%29.aspxManage linked mailboxes
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Applies to: Exchange Server 2013
Topic Last Modified: 2012-11-27
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Use the Shell to create a linked mailbox
This example creates a linked mailbox for Ayla Kol in the CONTOSO Exchange resource forest. The FABRIKAM domain is in the account forest. The administrator account FABRIKAM \administrator is used to access the linked domain controller.
New-Mailbox -Name "Ayla Kol" -LinkedDomainController "DC1_FABRIKAM" -LinkedMasterAccount " FABRIKAM\aylak" -OrganizationalUnit Users -UserPrincipalName aylak@contoso.com -LinkedCredential:(Get-Credential FABRIKAM\administrator)
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